The Rwanda scheme is at the centre of the government's strategy to stop illegal migration and is being watched closely by other countries considering similar policies.
But last month, the United Kingdom's Supreme Court ruled that the plan would violate international human rights laws enshrined in domestic legislation.
The opposition Labour Party, which has a double-digit lead in the polls, plans to ditch the Rwanda policy if it wins.
[1/5]British Home Secretary James Cleverly and Rwandan Minister of Foreign Affairs Vincent Biruta sign a new treaty, in Kigali, Rwanda, December 5, 2023.
The first flight was scheduled to go last summer but was cancelled at the last moment because of legal challenges.

UK interior minister signs new Rwanda treaty to resurrect asylum plan